This invention relates to apparatus capable of feeding marginally punched record material and, more particularly, to such an apparatus for use in a printing machine of the type comprising a platen, means for rotating the platen about its axis, at least one roller, a lever capable of manual movement between first and second positions, and means coupled between the lever and roller for maintaining the roller in engagement with the platen when the lever is in its first position and for maintaining the roller spaced a predetermined distance from the platen when the lever is in its second position.
Printing machines incorporating the above-referenced elements have been known for decades, as evidenced by U.S. Pat. Nos. 1,270,292 and 3,753,483. The latter patent also discloses a conventional tractor feed apparatus for use with a typewriter including the above-referenced elements.
It is, of course, well known that when loading and feeding non-marginally punched record material, such as ordinary plain paper, through a printing machine by a conventional platen-pressure roller arrangement, it is generally necessary to maintain the roller or rollers in engagement with the platen to define a nip or nips for positive feeding. It is also well known that the rollers may be moved away from the platen in order to correctly align the record material when loaded, or to facilitate removal of the material.
When feeding marginally punched record material, such as computer forms paper, it is generally necessary to use a feeding apparatus different that the conventional platen-pressure roller arrangement. The two most common types of feeding apparatus for this type of record material are the pin-feed apparatus and the tractor feed apparatus. As indicated above, an exemplary tractor feed apparatus is disclosed in U.S. Pat. No. 3,753,483. An exemplary pin-feed apparatus is disclosed in my co-pending application Ser. No. 660,555 entitled PIN FEED APPARATUS and assigned to the assignee of the present invention. In both the pin-feed apparatus and the tractor feed apparatus, the pressure rollers must necessarily be disengaged from the platen during feeding. To this end, a lever and associated structure of the type generally described above is provided in the printing machine for enabling the rollers to be manually retracted and disengaged from the platen. However, during loading of the marginally punched record material onto the feeding apparatus (pin or tractor), it has been found beneficial to position the lever so that the rollers are again engaged with the platen. In this manner, the platen knobs may be manually rotated to positively advance the record material through the nip between the platen and rollers to the location of the pin or tractor assembly, whichever the case may be.
Very recently, it has become the practice to utilize one or more guide racks with a feed apparatus for marginally punched record material. This is primarily due to the propensity of the material to bend at its periodic line perforations, the material capable of being torn along such perforations in order to separate the material into individual sheets. When bending, the outfeed of material may tend to get caught into the infeed. This is especially true when the feeding apparatus has a reverse feed capability as is the case with the pin feed apparatus disclosed in my above-mentioned co-pending application Ser. No. 660,555 . A guide rack is used to positively segregate the infeed and outfeed record material.
In order to facilitate loading of the marginally punched record material into the printing machine and onto the feed apparatus, the guide racks used to date have been made pivotal between a first or loading position in which the record material may be loaded, and a second or feeding position in which record material fed by the feed apparatus is guided along the rack away from the machine.
The normal manner of readying the printing machine and feed apparatus equipped with a guide rack of the above type is to pivot the rack to its first position and move the lever to a position engaging the rollers against the platen. Then, the marginally punched record material is loaded into the machine and through the nip between the platen and rollers. The platen is then manually rotated until the record material is at a location to be engaged by the feed apparatus. The record material is then so engaged, the lever moved to a position disengaging the rollers from the platen, and the rack pivoted to its second position.
It would be desirable to provide a feed apparatus for marginally punched record material of the type equipped with a guide rack wherein the number of required manual operations is reduced. More specifically, it would be desirable if the manual movement of the guide rack could cause the desired corresponding movement of the pressure roller or rollers.